Aerosol dispenser with valve cleanout mechanism



2. il f5- June 8, 1965 s, FERGUSQN 3,187,953

AEROSOL DISPENSER WITH VALVE CLEANOUT MEGHANISM Filed Aug. 29, 1962 2 Sheets-Sheet l 22- 203 y Z ffii f 5 E /7 v i Z 4 27 INVENTOR. 5.4m .5. Fazer/fad June 8, 1965 c. s. FERGpsoN 3,187,953

AEROSOL DISPENSER WITH VALVE CLEANOUT MECHANISM Filed Aug. 29, 1962 2 Sheets-Sheet 2 3,187,953 AEROSOL DISPENSER WITH VALVE CLEANOUT MECHANISM Carl S. Ferguson, Fort Lauderdale, Fla., assignor to A. E.

Staley Manufacturing Company, Decatur, Ill., a corporation of Delaware Filed Aug. 29, 1962, Ser. No. 220,304 1S Claims. (Cl. 222-149) This invention relates to improvements in aerosol dispensers and is more particularly concerned with an improved valve having a self-cleaning mechanism incorporated therein.

During recent years aerosol dispensers have been adapted for use in dispensing virtually every imaginable household liquid and/r solid which is dispersible in a liquid vehicle. Almost all of these materials leave some residue in ther nozzle and the passages leading to the nozzle of the aerosol dispenser, and many materials such as starch pastes, enamels, lacquers, oor waxes, etc. leave residue which form hard, tenacious deposits that rapidly clog the valve passages and nozzles unless extra precautions are taken. Frequently, such deposits of the material do not dissolve in the liquid or liquid vehicle subsequently dispensed, and the result is that the dispen sers, with its contents, must be discarded or, at best, must be carefully cleaned before use is resumed.

It is a principal object of the present invention, therefor, to provide an aerosol dispenser having a valve mechanism which incorporates therein provision for cleaning United States Patent the nozzle and the passages leading to the nozzle of any i residue of the active ingredient left therein at the end of each dispensing operation.

' It is a more specific object of the invention to provide an aerosol valve assembly having a self-cleaning mechanism wherein a small amount of propellant is trappedduring the operation of the valve and automatically released when the valve closes so as to clean out substantially all residual active ingredient before the residual material has time to solidify in Ithe nozzle or passages leading to the nozzle,

A still more specific object of the invention is the provision of a small auxiliary chamber which is'connected -to the valve chamber so that in one positionthe valve stem is sealed off from the ingredient to be dispensed and communicates with the small chamber so as to admit propellant thereto while in a second or dispensing V.position the valve stem is `sealed off from the small `chamber and communicates with the ingredient to be dispensed.

Another object of the invention is the provision of a relatively small chamber combined with the valve chamber which is of small volume relative to .the volume of the aerosol head space and which is in communication Wit-h the valve stem when the stem is in its venting position and with a second valve communicating with the head space above the liquid to be dispensed, which second valve is arranged in such a manner relative to the valve stem that it is closed when the valve stem is in its venting position and the chamber is sealed off from the aerosol head space. When the valve stem is in its dispensing position the second valve is open and a portion of lthe propellant in the aerosol head space is free to enter the small chamber. When the valve stem is moved to the rst or venting position the propellant 3,187,953 Patented June 8, 1965 trapped `in the small chamber which is now sealed off from the aerosol head space is free to escape through the dispensing nozzle, thereby clearing the nozzle and stem passages of any residue of the material being dispensed with relatively little waste of propellant due to the small volume of the chamber in comparison with the aerosol head space.

' It is a still further `object of the invention to provide a valve and chamber arrangement having a maximum transverse diameter less than the diameter of the opening at the top of the dispenser through which .the valve assembly is introduced `in order that the structure which forms the small chamber can be introduced into the dispenser through the top opening during the assembly, and preferably having a portion of the valve assembly which is within the dispenser disposed within the small chamber.

These and other objects and advantages of the invention will be apparent from a consideration of the several forms of aerosol dispensers which are shown by way of illustration in the accompanying drawings wherein:

FIGURE lis a side elevation, with portions broken away, of lan aerosol-type container having embodied therein a valve structure which incorporates the principal features of the invent-ion;

FIGURE 2v is a vertical section through the valve assembly of FIGURE 1, to an enlarged scale, and with the valve in normal closed or non-operating position;

FIGURE 3 is a cross section similar to FIGURE 2 with the valve in lthe open or operating position;

FIGURE 4 is a cross section taken on the line 4-4 of FIGURE 2;

FIGURE 5 is a vertical section taken through the valve assembly of a modified form of the invention, the valve being shown in the closed position;

FIGURE 6 is a ver-tical section similar to FIGURE 5 with the valve shown in the open or operating position;

FIGURE 7 is a vertical section similar to FIGURE 2,

illustrating a further modification of the invent-ion, thel ,valve being shown in the closed or non-operating posi- FIGURE l0 is a fragmentary section similar to VFIG-y URE 9 with the valve shown in open position.

Referring rst to the form of the aerosol dispenser which is shown in FIGURES 1 to 4 of the drawings, there is illustrated an aerosol-type container 10 having a top opening 11 with a closure panel 12 in which there is mounted a dispensing valve and nozzle assembly 13. The container 1li is adapted to receive the active ingredient orliquid material 14 which is to be dispensed and the propellant or pressurized fluid which is confined in the headspace 15 between the top of the active ingredient 14 and the closure panel 12 in the top opening 11 of the container.

The nozzle and valve assemblyV 13 comprises a spring pressedV valve stem 16 (FIGURE 1) which is slidably mounted in a bushing 17 secured on the top surface of the closure panel 112. The valve stem 16 has an axially extending conduit 18 (FIGURES 2 and 3) which terminates 3 4 at the top or outer end in a dispensing nozzle 20 and-at the bottom or inner en-d in the port 21 through which the material to be dispensed passes. The valve stem 16 has an inner section 22 of enlarged diameter which i-s seated in an enlarged portion of the bore of the bushing17 and which provides an outer shoulder 23 cooperating with an internal shoulder in the bushing 17 to limit the outward movement of the stem. .It also provides an inner shoulder 24 which is adapted to seat against the flanged top 25 lof the valv-e body 26 so as to form a complete seal therewith when the valve stem 16 is depresse-d as in FlG-URE 3. A dip tube 27 extends from the valve body 26 to a point .adjacent the bottom of the container and provides a passageway for the material to be dispensed, the latter, .of cou-rse, being forced into the tube 27 by pressure of the propellant on the top surface of the liquid ingredient 14.

The valve body 26 has a top opening 28 which is normally closed by an inverted cup-shaped valve member 30 against the top surface of which the bo-ttom end of the valve stem 16 abuts. Valve member 30 is urged into closed position by a compression spring 31. The valvey spring 31 is seated at its lower end on a disc 3-2 xed in the valve body Z6 and having a central aperture 33 iior .accommodating a push rod 34 which depends from the bottom of the valve seal member 30. The push rod 34 extends through the aperture 33 Vand is provi-ded with ilexible sealing members 35. The lower end of the push rod 34 extends into a small chamber 36 at the bottom end of the valve body 26 andthe chamber 36 has ports 37 in the side Wall which com-municate with the larger chamber 38 formed by the housing 40. The housing 40 encloses the valve body 26 and is supported from the top Vof the container closing disc 12.

The valve body 26 is provided withfa bottom extension 41 which may be integral therewith as shown and which has .a bor-e 42 in which la small valve member 43 is seated.

The valve member 43 is urged upwardly by a spring 44 so as to normally close the upper end portion 45 of the bore 42 in the extension 41. The valve member 43 has a stem 46 which is axially aligned with the push rod 34 so that when the push rod 34 is depressed, the bottom end engages the valve stem 4.6 and depresses the valve mem-` ber 43 ,allowing propellant to enter from the head space 15 through the aperature 47 at the bottom of the housing 40. The propellant enters through the passageway 45 into the chamber 36 and throughthe ports 37 into th-e chamber 38 so that aV small amount of propellant is accumulated in the chamber 3'8 while the valve stem 1:6 is depressed .and the top opening of the valve body 26 is sealed by the shoulder 24 on the valve stem'.

In using the dispenser, downward pressure is applied to the nozzle to depressV the' valve stem 16. When t-he valve stem 16 is depressed the shoulder 24 seals off the opening in the top ofthe valve body 26 which resuits in passage of the liquid ingredient through the dip tube 27, the valve body 26, the por-ts 21 and into the discharge .passage V1S of the valve stem'1'6 and iinally through the nozzle 20. The depression of the `valve stem` 16 also depresses the valve 43 which permits propellant to pass through the aperture 47, past the small valve 43 and `into the chamber 3:8. where it is trapped by closing of the valve 43 upon release of the downward pressure on the valve stem 16. When the valve stem 16 moves upwardly after a dispensing operation, the ports 21 are opened and provide communication between the chamber 38, the passageway 18 in the stem 16 and the nozzle 2t) so that any accumulati-on of liquid in the valve stem passagewayin the nozzle 20 is blown out and removed by the accumulated propellant in the chamber 38 which escapes through the nozzle4 20, thus cleaning out the nozzle and Aadjoining passageway automatically as the dispensing operation is discontinued. The cycle is, of course, repeated for each dispensing operation with the amount of propellant which Y 4 is used for cleaning the nozzle at the end of each operation being relatively small.

A modication of the invention is shown in FIGURES 5 and 6 of the drawings, with the valve assembly 59 only lbeing shown, the container and nozzle being broken away and it being understood that the valve assembly 5@ is incorporated in an aerosol-type container in the same manner as shown in FIGU-Rll of the drawings.

The valve assembly Sii comprises a spring pressed valve stem 51 which is slidably mounted in a bushing 52 secured in upstanding relation on t-he top of the aperture-d container closure panel 53. TheY valve stem S1 has an axial conduitor passageway 54 terminating at its top in a nozzle (not shown) and at its lower end in entrance ports 55. The inner or lower portion 56 of the valve stem 5.1 is of reduced cross section and extends at its lower end in slidingv relation into the cylindrical neck forming portion 57 of the valve body 58. The valve body 5S has a bottom opening 59 formed by a ilange on which the upper end of the dip tube 66 is secured so as to provide for passage into the valve body 5d of liquid ingre-dient from the bottom of the container (not shown). The valve body 56 houses a valve spring 61 having an inverted cup-.shaped valve member 62 which is adapted to close the top opening 63 formed by the neck portion 57 and against the top surface of which the bottom end of the valve stem 51 is adapted to bear when the latter is depressed a suicient distance to permit the flow of ingredient through the ports 55.

A housing 64 extends between the valve body 58 and the container top closure panel 53 so as to form a small compartment 65 through which the lower .section 56 of the valve stem 51 extends and which communicates with the axial passageway 54 in the valve stem 51 through one or more radially `extending ports 66 when the valve stem 51 is in normal non-operating position as shown in FIG- URE 5. The reduced lower section 56 of the valve stem 51 provides an abutment shoulder 67 which seats against the upper surface of an apertured cup-shaped cap member 68 on the upper end of a compression spring 76 which is enclosed in the housing 64. The housing 64 has an opening 71`in the bottom wall which communicates with the head space'in the container and which is normally closed by a small valve assembly 72 of the same charlacter as the valve 43 in FIGUR-ES 2 and 3. The valve 72 4has an upstanding stem 73 which is in the path of an arm 74 mounted on the valve stern section 56.

. In operating this form ofthe dispenser, the valve stem 51 is normally held in non-operating position by the compression spring 70 in the chamber 65 with the passageway or opening 63 between the `chamber 65 and the valve bodySS being closed by the lower end portion of the valve stem section 56. The opening 71 between the chamber 65 and the head space is also normally closed by the valve assembly 7.2 and the conduit or passageway S4 in the valve stem 51 is closed at its lower end which is disposed in the neck portion 57 of the valve body 58. When the valve stem 51 is depressed, the lower end of the same engages with the valve member 62 and depresses .the same so as to provide communication between the dip tube 60, the valve body 58 and the conduit 54 through the ports 55 which are moved to open position as shown in FIG- URE 6. The depression Vof the valve stem 51 carries the arm 74. into engagement with the valve stem 73 and opens the valve 72 so as to allolw propellant to enter into the chamber 65 where vit is trapped when the pressure on the Valve stem 51 is released and the arm 74 rises, allowing the valve 72 to close. The upward movement of the valve stem 51 closes the ports 55 and the passageway 63 in the top of the valve body S3 so as to cut oi the flow of ingredient through the dip tube 6d; t The upward movement of the valve stem 5,1 opens the ports 66 and provides communication between the small chamber 65 and the nozzle so as to allow the propellant trapped in the chamber 65 to escape through the'conduit 54 and the nozzle, automatically cleaning out any residual material which may have remained therein when the ilow of ingredient is stopped. Y

A further modiiication of the valve assembly is shown in FIGURES 7 and 8. This form of the valve assembly is similar to the form shown in FIGURES 5 and 6 and corresponding parts are indicated by the lsame `numerals primed. In this form of the valve assembly the lower section 56 of the Valve stem 5i is radially slotted at 75 to provide ports for passage of ingredient from the valve body 58 into the axial passageway 54'; The valve stem section 56 carries an arm 74 for engaging the valve stem 73 of the valve 72 in the small housing 64. The arm 74 extends radially from a collar 76 which is mounted on the stem section 56 and which is of inverted, truncated cone shape. The collar 76 provides a lower abutment shoulder 77 which is located so that it will seat on the upper edge 78 of the neck portion 57 of the val-ve body 58 and form a seal therewith when the valve stem 5l is depressed or moved to operating or dispensing position, as shown in FIGURE 8.

The Aoperation of the form of the dispenser shown in FIGURES 7 and 8 is the same as in the form-ot the dispenser shown in FIGURES 5 and 6 and described in connection with these figures. When the valve stem 51' is depressed against the force of spring 70 for dispensing the contents of the container the collar 76 moves down to bring the lower abutment edge '77 into engagement with the edge 7S of the valve body 58 and thereby provides an additional seal between the small compartment 65 and the valve body 5S so as to insure that the ingredient will not escape into the compartment 65 during a dispensing operation.

A still further modification of the valve'assembly of FIGURES 5 and 6 is illustrated in FIGURES 9 and 10. In this form, opening 7.1 in the bottom wall of the small compartment and the small valve 72 is eliminated. A passage-way for entrance of propellant into the small compartment or chamber is provided by forming an axial slot Si) in the lower end 56" of the valve stem 51" and an opening 81 in the neck portion 57" of the valve body 5S which are arranged as shown in open position in FIGURE 9 and in closed position in FIGURE l0. The operation of this form of the valve assembly is the same as in lthe form thereof shown in FIGURES 5 and 6 with the passageways Si) and 81 admitting propellant into thesmall compartment while the ingredient is being dispensed and closing the connection between the compartmentand the head space when the dispensing of the ingredient is discontinued by retraction of the valve stem to 4the nonoperating position.

k While particular materials and specific details of construction are referred to in describing the several forms of the dispenser which are illustrated, it will be understood that other materials and equivalent details of construction may be resorted to within the spirit of the invention.

I claim:

11A valve assembly for an aerosol container which has a top opening and a closure member therein, a valve stem slidably mounted in a bushing secured on thev closure member, a valve -body mounted in the container and having a top opening into which t-he lower end of the valve stem extends, a spring pressed valve member in the valve body which is normally in position to close said valve body top opening and which is engaged by the lower end of the valve stem and moved to open position when the valve stem is depressed, said valve stem having an axial passageway communicating with a spray nozzle at the upper end and ports at the lower end which open within the valve body when the stem is depressed for passage of the material to be sprayed, a dip tube connected to the valve the aerosol container, a valve member normally spring biased into a position to close said last mentioned opening, and means movable with the valve stem to engage said last mentioned va-lve member and move it to open position when said valve stem is depressed, means movable with the valve stem to close the top opening in the valve body from access to said small housing, when the valve stem is depressed whereby the material to be dispensed is discharged from the valve body through the ports and into the passageway in the valve stem, said valve stem, when in retracted position, placing the ports at the lower end thereof in communication with said housing so as gto allow propellant trapped therein to escape through the val-ve stem and nozzle.

2. A valve'as'sembly for an aerosol container which has a top opening and a closure member therein, a valve stem slidably mounted in a bushing secured on the closure member, a valve body mounted in the container and having an opening into which the lower end of the valve stem extends, a spring pressed valve member in the valve body which normally closes said valve body opening and which is engaged by the lower end of the valve stem and moved to open position when the valve stem is depressed, said valve stem having an axial passageway communicating with a spray nozzle at the upper end and ports at the lower end which open within the valve body when the stem is depressed for passage of the material to be sprayed, a dip tube connected to the valve body, means forming a small chamber connected to the valve body and having an opening communicating with the head space in the aerosol container, a valve member normally positioned to close said last mentioned opening, and means movable with the valve stem to move said last mentioned valve member to open position when said valve stem is depressed, means movable with the valve stem to closeY the opening in the valve body from access to said small chamber means, when the valve stem is depressed whereby the material to be dispensed moves through the valve body and the ports in the valve stem, Vand said valve stem, when in retracted position, having means connecting the axial passageway with the small chamber so as to allow propellant trapped therein to escape through the having an opening communicating with therhead space in valve stem and nozzle. Y

3. A valve assembly as recited in claim 2 with the lower end portion of said valve stem being reduced in cross section to provide a peripheral shoulder for sealingly engaging with the margins of the valve body around the opening therein.

4. A valve assembly as recited in claim 2 with said valve stem extending through said small chamber forming means.

5. A Valve asembly as recited in claim 2, with said small chamber forming means having aligned openings through which said valve stem extends with one of said A,openings constituting a passageway into the valve body which is normally closed by said valve stem.

6. A valve assembly for an areosol container which has a top opening and a closure thereofor, a valve stem slidable in a bushing mounted in the closure member, a valve body in the container and having a top opening into which the lower end of the valve stem extends a spring pressed valve member in the valve body which normally closes said valve body top opening and which is engaged by the lower end of the valve stem and moved to open position with the valve body when the valve stem is depressed, said valve stern having an axial pasageway communicating with a spray nozzle at the upper end and ports at the lower end which open within the valve body when the stem is depressed for passage of the material to be sprayed, a dip tube connected to the valve body, a housing forming a smallchamber surrounding the valve body and having an opening communicating with the head spaceV in the aerosol container when the valve stem is depressed, a valve member normally positioned to close said last mentioned opening, and means movable with the valve stem to open said last mentioned valve member when said valve stem is depressed, means movable with the valve stem to close the top opening in the valve body when the valve stem is fully depresse-dto permitpassage of the material to be dispensed through the valve stem, and said valve stem, when in retracted position only, having the lower end of its axial passageway in communication with the small chamber so as `to allow propellant trapped therein to pass through the valve stem and'nozzle.

'7. A valve assembly for an aerosol container which has atop opening and a closure member therefor, a valve stem slidably mounted in a bushing secured on the closure member, a valve body mounted in the container and having a top opening into which the lower end of the valve stem extends, a spring pressed valve member in the valve body which is normally positioned to close said valve body top opening and which is engaged by the lower end of the valve stern and moved to open position when the valve stem is depressed, said valve stem having an anxial passageway communicating with a spray nozzle at the upper end and ports at the lower end which open within the valve body when the stern is depressed for passage to the nozzle of the material to be sprayed, a dip tube connected to the valve body, a small housing surrounding the valve body and having an opening communicating with the head space in the aerosol container, said valve body having an extension on the bottom thereof with a bore which communicates at one end with the opening in the housing and at the other end with a chamber formed in the bottom of the valve body which has openings providing communication with said housing, a spring pressed valve member normally closing the bore in `said valve body extension, a push rod on the valve member in said valve body which extends through a sealing member in the valve body and is aligned for movement with the valve member in the body extension and is arranged to move thesame to open position when said valve stern is depressed, means movable with the valve stem to close the top opening in the valve body when the valve stem is depressed and permit passage of the material to be dispensed through the ports in the valve stem, said valve stem, when in retracted position, placing the ports on the lower end in communication with said housing so as to allow propellant trapped therein to escape through the valve stem and nozzle.

8. ln an aerosol dispenser, a valve assembly comprising a valve body disposed within the top of the dispenser and having a discharge opening and a connection with a dip tube, a spring pressed valve member for closing said discharge opening and a valve stem with an axial passageway terminating at the outer end at a nozzle disposed outside the dispenser and at the inner end in ports which are openV within the valve body when the Y valve stem is depressed suicient to engage the inner end with the valve closing member and move the same to open position, means forming a relatively small auxiliary chamber having a connection with the valve body, valve means connecting said auxiliary chamber with the head space in the dispenser which valve means is opened by movement of the valve stem when the valve stem is depressed and closed when the valve sternV is released, and means forming a connection between the passageway in the valve stem and said auxiliary chamber which is closed, when the valve stem is depressed and open when it is released so as to automatically discharge a small amount of the propellant through said passageway after each spraying operation.

9. In an aerosol dispenser, a valve assembly comprising a valve body disposed within the dispenser and having a discharge opening, a spring pressed valve member for 'closing the opening, a dip tube connected with 'said valve body, and a valve stem with an axial passageway terminating at the outer end at a nozzle and at the inner end opening within the valve body when the valve Vstem is depressed sufficient to engagethe inner end with theY valve closing member and move the same to open position within the valve body, means forming a relatively small auxiliary chamber having a connection 'with the valve body, valve means connecting said auxiliary chamber with the head space in the dispenser which is opened by movement of the valve stem when the valve Vstem is depressed and closed when the valve stem is released, and means forming a connection between the axial passageway in the valve stem and said auxiliary chamber which is closed when the valve stern is depressed and open when the valve stern is Vretracted so as to automatically discharge a small amount of the propellant through said axial passageway after each spraying operation.

10. In an kaerosol dispenser, a valve assembly comprising a valve body disposed within the dispenser and having a discharge opening and a dip tube connected thereto, a spring pressed valve memberfor closing the opening and a valve stem with an axial passageway terminating at the outer end at a spray nozzle and the inner end opening within the valve body when the valve stern is depressed suflicient to engage the inner end with the valve closing member and move the same to open position, means forming a relatively small auxiliary chamber having a connection with the valve body, valve means connecting said auxiliary chamber with the head space in the dispenser which is opened by movement of the valve stem when the valve stern is depressed and closed when the valve stem is released, and a radial passageway connecting the axial passageway in the valve stern and said auxiliary chamber which radial passageway is closed when the valve stem is depressed and open when it is released so as to automatically discharge a small amount of the propellant through said passageways after each spraying operation.

11. In an aerosol dispenser as recited in claim l0 and said auxiliary chamber forming means having top and bottom openings through which said valve stem extends Evitdh the bottom opening communicating with the valve 12. In an aerosol dispenser as recited in claim lil, and a compression spring seated in said auxiliary chamber and engaging a closure member on said valve stem for closingV the top opening in said auxiliary chamber.

13. In an aerosol dispenser as recited in claim llt), and

`said auxiliary chamber forming means having top and bottom openings through which the end portion of said valve stem extends, the bottom opening being defined by a ange which is joined to a cooperating flange on the valve body and forms a connecting passageway between the valve body and the auxiliary chamber, and said valve stern having an end portion which extends into said connecting passageway with radially extending ports which are opened and closed by movement of the valve stem in the connecting passageway for placing the axial passageway in the valveA stem in communication with the valve body and the auxiliary chamber alternately.

14. In an aerosol dispenser as recited in claim 13, and a collar on said valve stem which seals the connecting passageway between the valve body and the auxiliary chamber when the valve stem is depressed,

15. In an aerosol dispenser, a valve assembly comprising a valve body disposed within the dispenser and having a discharge opening, a spring pressed valve member for closing the opening and a valve stem slidably mounted in a bushing at said discharge opening, said valve stem ,having an axial passageway terminating at the outer end at a spray nozzle and the inner opening within the valve body when the valve stem is `depressed suilicient to engage the inner end with the valve closing member and move the same to open position, means forming a relatively small auxiliary chamber between the valve body and said bushing, said Vchamber forming means havstem extends, the bottom opening being connected to a neck forming portion of the valve body in which the end of the valve stem slides, a collar on said valve stem p which seals said neck portion when the valve stem is depressed, said auxiliary chamber having an opening into the head space in the dispenser, a valve in said opening which is operated by an arm extending from the collar on said vvalve stem so that it is closed when the valve stem is depressed and open when it is released whereby to automatically discharge a small amount of the propellant which is trapped in said auxiliary cham- 19 ber through said passageway after each spraying operation.

References Cited by the Examiner UNITED STATES PATENTS 10 RAPHAEL M. LUPO, Primary Erarm'rrer.

LAVERNE D. GEIGER, Examiner. 

9. IN AN AEROSOL DISPENSER, A VALVE ASSEMBLY COMPRISING A VALVE BODY DISPOSED WITHIN THE DISPENSER AND HAVING A DISCHARGE OPENING, A SPRING PRESSED VALVE MEMBER FOR CLOSING THE OPENING, A DIP TUBE CONNECTED WITH SAID VALVE BODY, AND A VALVE STEM WITH AN AXIAL PASSAGEWAY TERMINATING AT THE OUTER END AT A NOZZLE AND AT THE INNER END OPENING WITHIN THE VALVE BODY WHEN THE VALVE STEM IS DEPRESSED SUFFICIENT TO ENGAGE THE INNER END WITH THE VALVE CLOSING MEMBER AND MOVE THE SAME TO OPEN POSITION WITHIN THE VALVE BODY, MEANS FORMING A RELATIVELY SMALL AUXILIARY CHAMBER HAVING A CONNECTION WITH THE VALVE BODY, VALVE MEANS CONNECTING SAID AUXILIARY CHAMBER WITH THE HEAD SPACE IN THE DISPENSER WHICH IS OPENED BY MOVEMENT OF THE VALVE STEM WHEN THE VALVE STEM IS DEPRESSED AND CLOSED WHEN THE VALVE STEM IS RELEASED, AND MEANS FORMING A CONNECTION BETWEEN THE AXIAL PASSAGEWAY IN THE VALVE STEM AND SAID AUXILIARY CHAMBER WHICH IS CLOSED WHEN THE VALVE STEM IS DEPRESSED AND OPEN WHEN THE VALVE STEM IS RETRACTED SO AS TO AUTOMATICALLY DISCHARGE A SMALL AMOUNT OF THE PROPELLANT THROUGH SAID AXIAL PASSAGEWAY AFTER EACH SPRAYING OPERATION. 